Display screen or portion thereof with transitional graphical user interface



FIG. 1 is the first image in a sequence for a display screen or portion thereof with transitional graphical user interface showing our new design;

FIG. 2 is the second image thereof;

FIG. 3 is the third image thereof;

FIG. 4 is the fourth image thereof;

FIG. 5 is the fifth image thereof;

FIG. 6 is the sixth image thereof;

FIG. 7 is the seventh image thereof;

FIG. 8 is the eighth image thereof;

FIG. 9 is the ninth image thereof;

FIG. 10 is the tenth image thereof;

FIG. 11 is the eleventh image thereof;

FIG. 12 is the twelfth image thereof;

FIG. 13 is the thirteenth image thereof;

FIG. 14 is the fourteenth image thereof;

FIG. 15 is the fifteenth image thereof;

FIG. 16 is the sixteenth image thereof; and,

FIG. 17 is the seventeenth image thereof.

The outermost broken lines in the drawings represent a display screen or portion thereof and form no part of the claimed design. The remaining broken lines in the drawings illustrate portions of the transitional graphical user interface that form no part of the claimed design.

The appearance of the transitional graphical user interface sequentially transitions between the images shown in FIGS. 1 through 17. The process or period in which one image transitions to another forms no part of the claimed design. 

CLAIM We claim the ornamental design for a display screen or portion thereof with transitional graphical user interface, as shown and described. 